Garmin Does ADS-B

The avionics manufacturer is creating innovative ways to make this new, remarkably complex technology the pilot’s best friend.

Garmin 750

Garmin 750

Garmin 750

As the FAA is building out the infrastructure for its nationwide automatic dependent surveillance – broadcast (ADS-B) surveillance network, avionics manufacturers are beginning to market in earnest the gear that will take advantage of the benefits of this new technology. As this happens, it’s becoming apparent that there are greater challenges to ADS-B and greater potential rewards than anyone had imagined when the concept was hatched more than a decade ago.

The year 2020 might seem a long way away to you, and it is, but only kind of. That is, of course, the year that every airplane operating in the U.S. National Airspace System (NAS) is going to have to be ADS-B compliant. Experience with previous mandatory equipage dates, such as that with terrain awareness nearly a decade ago, should tell us that 2020 will come sooner than we’re collectively ready for it to come.

The bottom line is that by Jan. 1, 2020, everybody who flies in what is essentially Mode C airspace will be required to be ADS-B equipped. The scale of the plan is massive, and as a part of that plan, we’ll all be required to have ADS-B Out (the broadcast part). The fully functional ADS-B system depends on that “Out” capability.

Today there's some benefit to be gotten with ADS-B In only. With that function, we can see some other ADS-B traffic and get free FAA weather products, including Nexrad radar, metars and TAFs, winds aloft and more.

ADS-B is not future tech. It's already working, and we at Flying have been using the technology in one form or another for a few years now. We recently tested and reported on some of the first ADS-B receivers, including a portable, battery-powered receiver from Appareo, the Stratus, that works great and costs less than a thousand dollars with free weather as part of the deal. Expect to see more innovative ADS-B products roll out — a number of them are already here.

**On an ADS-B Mission **
While a number of avionics manufacturers have released compelling ADS-B products, one company, Garmin International, has recast itself as an ADS-B company, working to leverage this new technology into every product in which it makes sense. Right now the company is actively developing or has recently launched more than a dozen major products for aviation, and this is counting only the ones of which we're aware. Many of those actively rely on ADS-B for the advanced functionality of the equipment.

While this sounds great, ADS-B has proved so complex a technology that there will be education and training challenges, both for Garmin and for its customers. The challenge for pilots is in keeping track of what’s going on in the cockpit. The challenge for Garmin is in explaining all of it. After all, before long most pilots will find themselves having to work this equipment, or something like it, in flight. Understanding how it works and what it will and won’t do is critical. Toward that end, looking at what Garmin is doing across its product lineup is instructive.

GDL 88 and GDL 39
Garmin's two brand-new ADS-B solution boxes are the GDL 88 and GDL 39. The 88, which can be purchased in a variety of ways depending on customer needs, is a remote-mount permanently installed unit that provides ADS-B In, Out or In/Out coverage. With GDL 88 ADS-B Out installation or better, an airplane will meet the FAA 2020 mandate. The 88 will work with a number of displays from a number of manufacturers, but it works its most remarkable magic when paired with the Garmin GTN 750 multifunction display. Prices for the GDL 88 start at $3,995. The price goes up to just under $6,000 for a compliant system with a WAAS receiver if needed. For those prices, the promise of ADS-B is great.

For those with a smaller budget, Garmin's GDL 39 is a great option. The GDL 39 is a portable ADS-B receiver that gets free ADS-B weather and ADS-B traffic too. The unit contains both a WAAS receiver and an ADS-B receiver. It connects to an iPad via a Bluetooth connection or to the Garmin 796 (with Bluetooth on the way) or GPSMap 696 and Aera 500-series handhelds via a dedicated cable. As far as iPad apps are concerned, the GDL 39 currently works only with Garmin Pilot, the company's excellent all-in-one iPad app that gives you moving map, charts, weather, terrain alerting, airport and FBO info, and more. Making the connection was ­dirt-simple, and the performance of the GPS/WAAS ADS-B receivers was excellent. The GDL 39 sells for around $800 including accessories.

With the GDL 39 you can receive ADS-B weather transmissions when you’re in line of sight with an FAA ground station and display that weather on Garmin’s brand-new Garmin Pilot iPad app (more on that product in a bit). The weather, as we’ve written about before, is very good, though not quite as good as Sirius XM Weather. The big advantage of ADS-B weather is that you not only get most of the weather products you care about at reasonably good quality, but there’s no subscription, as there is for Sirius XM Weather, for instance. The downside is that, because it’s a ground-up system, you can’t always get reception. This is true for ADS-B weather in general, regardless of the receiver or whether it’s permanently installed or mounted or a portable unit. The weather you get with the GDL 39 is good, and the display of weather on Garmin Pilot on your iPad is excellent, with the weather information, animated Nexrad, graphical metars, winds and more shown on the main map page and also integrated into various airport information pages so you can check the weather without changing screens. The integration of ADS-B weather into Garmin Pilot is top-drawer.

Unlike a couple of competitors’ boxes, the GDL 39 provides in addition to weather ADS-B traffic information for display on the iPad or other devices. What traffic you will see varies tremendously based on a number of different factors, the most important of which is whether you are, to use the FAA’s term, participating in the ADS-B scheme. Those operators who get weather and traffic with ADS-B In (like with portable gear) but don’t transmit their ADS-B position information (ADS-B Out) don’t get the same benefits as participants get.

ADS-B as it stands today presents an incomplete traffic picture, and that’s the way it will stay until 2020. The picture, thanks to the FAA’s strange stance on providing traffic information, is far more confusing and incomplete than it needs to be. Because the feds are trying to encourage people to participate in ADS-B by installing ADS-B Out equipment, they have decided to not send traffic information via ground stations to airplanes with just ADS-B In, such as with a portable system like the GDL 39. To the many critics of the plan, the withholding strategy seems at worst a hazardous gamble designed to strong-arm operators into equipping, a plan that intentionally keeps critical and freely available safety data away from pilots. As a result of the FAA’s arbitrary restrictions, not to mention the small numbers still of ADS-B participants, it’s impossible to tell when you’re going to see traffic, if there’s traffic out there you’re not seeing, or whether the traffic you’re seeing is going to disappear just as suddenly as it appeared.

If you’re not yet participating, you’re going to get air-to-air traffic, so if there’s another ADS-B target, it will show up on your display. In our test of the GDL 39 at altitude, this function worked perfectly. When using the GDL 39 in a CJ, we didn’t see traffic that would normally be relayed through the ground station, because we were not participating (by having ADS-B Out).

There are a couple of other types of traffic you’ll get with ADS-B In only: If you pass near a participating ADS-B target, you’ll get traffic data from the ground station that that target is “lighting up.” But once you lose sight of that target, you lose sight of all the traffic it was sending along to you as well.

On our flight, for instance, we were passing near a 757. The pilot was getting traffic from the ground station he was in contact with. We could see that traffic through our portable ADS-B receiver, including nonparticipating ADS-B airplanes that are near a ground station (around 15 miles and plus or minus 3,500 feet from our altitude), but once we lost “sight” of the 757 we lost sight of all of his relayed traffic too.

When it comes to TIS-B traffic, which relies on certain FAA radar sites to relay traffic information, an ADS-B In-only operator will get some TIS-B traffic when he is in close proximity to ADS-B traffic that is receiving that TIS-B information. There is some indication this is so. When it is displaying traffic information from the GDL 39, Garmin Pilot will annunciate when this TIS-B reception is active. Garmin is working to provide even more annunciation on what traffic services the GDL 39 is currently receiving.

The display of weather and traffic worked beautifully on the GPSMap 796 that I tested as well, though you need a direct connection on that box.

Power Play
The full capability of the ADS-B system was strongly evident when using the ADS-B Out/In GDL 88 remote box playing on a GTN 750 multifunction touch-screen display. With the latest GTN software version 3.0, the touch-screen multifunction unit becomes a powerful traffic system that allows you to see ADS-B traffic in ways you'd never imagined.

For starters, ADS-B gives you all kinds of information that you don’t get from traditional traffic utilities, including N-numbers and direction of flight. You can also see what kind of target it is you’re looking at, ADS-B, TIS-B or primary radar relayed. Garmin’s panel-mount ADS-B traffic utilities when played through the latest Garmin display (the GTN 750) integrate existing active traffic utilities (like TCAS) with the new ADS-B data.

Relative Traffic
The most remarkable utility, though, is something you've probably never seen on a traffic display before.

With traditional traffic gear, we’re used to seeing a static view of airborne traffic. That is, we see a snapshot of where everybody is at that given moment in time. With Garmin’s patent pending relative-motion traffic display, which the company calls TargetTrend, you see not just where the traffic is, but where it is going to be over time, with the predicted track of the target airplane projected forward in time so you can see what kind of a threat it really is, or isn’t. This is, after all, what we really care about, where traffic is going to be when it really matters.

The core idea behind relative motion will twist your brain in a knot if you’re not careful, or even if you are. Take for example the idea of where our airplane and potential conflicting traffic are headed and throw that idea out the window.

Let’s say we’re flying 200 knots over the ground and an airplane ahead of us is traveling in the same direction but going 100 knots slower. Relative traffic begins with the idea that it doesn’t really matter in what direction the target is traveling; that’s immaterial. All that matters is that it is, relatively speaking, approaching us at 100 knots. It might for all intents and purposes be flying right at us. That’s the basic concept behind relative motion, and once you put that idea into action by projecting where traffic will be based on your relative motion and theirs, you get the kind of information you really want. One Garmin test pilot told me that a flight down in the Los ­Angeles basin on a busy afternoon revealed in no uncertain terms that the traffic they’d previously (with old-fashioned absolute motion displays) thought of as threatening wasn’t, at least not when viewed through the lens of relative motion. Moreover, the traffic they’d have previously ignored suddenly was exposed to be actually threatening.

I flew this brand-new gear last month out of Garmin's Salem, Oregon, facility in the company's King Air C90 and had a chance to see firsthand how relative motion works. I'll never see traffic the same way again.

The King Air was outfitted with the GDL 88 remote-mount ADS-B unit displaying on GTN 750 display and integrating a Garmin active traffic system. After taking off from Salem we tracked a Garmin Mooney 201 also equipped with ADS-B that had taken off shortly before us. With the GTN display of the GDL 88 data, we were able to track not only where the Mooney was but where it was going to be, monitoring its projected track to see where our closest point of threat was. When an active threat is identified, the GTN display of ADS-B data shows a dashed green line leading to a solid green line showing a potential point of collision over time. The displays showed us what we needed to know to avoid a conflict.

Relative motion is a revolution. It tells you not what is happening in a static world but what is happening in the real world. It’s cool stuff, and it’s only going to get better.

The bottom line is that ADS-B is here, and with a full-up permanent ADS-B In/Out system, there are some remarkably attractive benefits waiting for pilots to equip, and those benefits — ADS-B traffic and free weather — will only get more attractive as time goes on and more airplanes equip.

As far as weather is concerned, ADS-B offers a compelling and ­cost-effective alternative to paying for subscription satellite weather, a welcome development.

When it comes to next-gen traffic, the message is clear. The future has officially begun. Looks like it’s time to get on board.